Wireless communication systems have the ability to support a finite amount of call traffic often referred to as a system's bandwidth. Each call made by a subscriber of a system places a demand on the available bandwidth. As the number of calls made by subscribers rises, the amount of cellular call traffic increases, using more and more of the available bandwidth. Because subscribers expect to be able to make calls on demand, as the volume of call traffic in an area increases, it may become necessary to expand the system's traffic throughput to insure subscriber expectations are met.
For systems making use of CDMA (Code Division Multiple Access) technology, system bandwidth can be increased by making use of additional carrier bands or channels. Each CDMA channel or carrier makes use of a frequency bandwidth of approximately 1.25 MHz. To increase the number of CDMA channels being used often requires the use of additional equipment. However because of customer or space requirements it may not always be conveniently possible to support the use of additional equipment.
Presently one modem frame provides support for up to four CDMA channels. In order to support a greater number of CDMA channels a second modem frame could be used. Unfortunately it is not always possible to install a second set of antennas to support the second modem frame. Therefore a cross modem frame combining technique that would allow an additional modem frame to be integrated into the system without requiring an additional set of antennas would be beneficial.